Condensed Consolidating Financial Information (Details) (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
ASSETS
Current assets	$ 76,637	$ 158,358
Property and equipment	1,835,609	1,572,845
Investment in subsidiaries (equity method)	0	0
Other assets	12,222	12,713
Total Assets	1,924,468	1,743,916
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities	187,577	156,735
Long-term liabilities	765,398	707,164
TOTAL Stockholders' Equity	971,493	880,017
Total Liabilities and Stockholders' Equity	1,924,468	1,743,916
Swift Energy Company (Issuer) [Member]
ASSETS
Current assets	0	0
Property and equipment	0	0
Investment in subsidiaries (equity method)	971,493	880,017
Other assets	0	0
Total Assets	971,493	880,017
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities	0	0
Long-term liabilities	0	0
TOTAL Stockholders' Equity	971,493	880,017
Total Liabilities and Stockholders' Equity	971,493	880,017
Swift Energy Operating, LLC (Guarantor) [Member]
ASSETS
Current assets	76,609	158,335
Property and equipment	1,835,609	1,572,845
Investment in subsidiaries (equity method)	0	0
Other assets	12,222	12,713
Total Assets	1,924,440	1,743,893
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities	187,578	146,728
Long-term liabilities	850,853	788,385
TOTAL Stockholders' Equity	886,009	808,780
Total Liabilities and Stockholders' Equity	1,924,440	1,743,893
Other Subsidiaries [Member]
ASSETS
Current assets	28	23
Property and equipment	0	0
Investment in subsidiaries (equity method)	886,009	808,780
Other assets	85,455	81,221
Total Assets	971,492	890,024
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities	(1)	10,007
Long-term liabilities	0	0
TOTAL Stockholders' Equity	971,493	880,017
Total Liabilities and Stockholders' Equity	971,492	890,024
Eliminations [Member]
ASSETS
Current assets	0	0
Property and equipment	0	0
Investment in subsidiaries (equity method)	(1,857,502)	(1,688,797)
Other assets	(85,455)	(81,221)
Total Assets	(1,942,957)	(1,770,018)
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities	0	0
Long-term liabilities	(85,455)	(81,221)
TOTAL Stockholders' Equity	(1,857,502)	(1,688,797)
Total Liabilities and Stockholders' Equity	$ (1,942,957)	$ (1,770,018)